Automatic telephone system



June 26, 1923. 1,459,860

7 w. T. POWELL AUTOMATI C TELEPHONE SYSTEM Filed July 15 1919' v R\HG\NG MACHINE.

CON HECTOR INVENTOR gmFREo T. POW L ATTORNEY Patented June 26,1923.

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WINFnnn T. rownnn, or soonnsrnn, nnw Yonmessro-won TO THE s'rnolvrnn'ne- CARLSON TELEPIFLONE MIANUFACTURIN A conieonerion osnnw "some it oo'i'virewa f or csocrinsrnn, new YORK,

AUTOJHATIC TELEPHONE SYS'TIEDZZ.

Application med. July 15, c

To all whom it may concern. I i Be it known that l, Wlnrniin T. POWELL. a citizen of the United States, residing at Rochester, in the county of Monroe and State of New York, have invented certain, new and useful Improvements in Ants inatic Telephone Systems, of which the following is a :full clear. concise, and. exact. description. v r

This invention relates to telephone systems and more particularly to telephone systems employing automatic switches for completing .connectio In such systems where automatic or machine ringing is employed to signalfcalled subscribers, the signaling ClQVlCd is always operated in thesaine 11121 111161 llIQSPQClJlVQ of the origin oi. the call. Veryc lrequent y arises that it is desirable that calls ori C) 111g from a particular source shall actuate the automatic ringing devicev tosignal the wanted station in a distinctivemanner, so.

that the called subscriber willpromptly answer the call. One instance-in which suchan arrangement Wlll he iound to be especially I useful, 1s in the case oil calls originating from the substation of a manager or superiir tendent of an industrial plant who desires that his calls shall he answered with s mcial promptness. i

The main feature of this invention is the provision of means to actuate the call ml of a wanted station ina partmular man ner when the call ori mates 'iIDDl onesource,

and toactuate said signal in another manner when the call is initiated iroin another present invention is incorporated. The portion of the drawing included withinthe dot ted enclosure at the left, represents line switch, that is. a switch individual to a line for extending this line to a preselectedidle trunk and a master switch for preselecting. The port1on o'lthe.

idle trunks foruse. drawing at the right ofythe line included within the dotted enclosure near the center of the drawing, diagrammatically rc zpre- 'sents a connector switch and at the lower ns between calling; and called subscribers, a

1919. seriaino.311,oe4.

rig'ht'hand corner 01 the drawing thereis shown a r nging machine which is common to a pluralityof connector switches in the system of thexpr'esent invention.

The present intention-has been shown in connection with a line switch, that is, a

switch ind'ividu'al'to the line, for connecting this l ne tooneozt a plurality of idle trunks, but it Will he understood that any well known selecting: means may be employed. to extendtlle calling line to onez of a group of connector switches in which the called line terminates. The line switch Sl'lQWl'lplilllhB presentin vention inay'he ot the structure substantially similar to that disclosed in the patent to A. E. Keith, No. 1,151,543. Aug. 24thy1915,

while the, connector switch may be-otthe structuresubstant ally similar to that shown .ith, etal, No. 815,176, 1s-

in the patent to sued Pit larch'lt-Btln 1906." I

The ringing machine has two interrupters mounted on a constantly rotating. shaft.

These interrupters or commutators are .pro-

vided with a plurality of conducting seg-. inents, oneo f them being provided withcfour conducting segments, and the other with twocoriducting segments for interrupting thesource of ringing current ina distinctive manner.

l diththis hrieii description of theapp'aratus employed; it is believed that theme yention will best he understoodhy describingfthe. method oi? establishing a connection from a calling substation Afwhich we will assume is that oi 'amanager or superintendent, to the called substation B. Since the call originates l rom a'substationwhioh requires prompt. response. distinctive ring-.

ing' current will he supplied to the called substation l3 in a manner tobe described.

ln initlatlng a call. the suhscrlber at Av removes h1s receiver from its SWlfCllhOOk whereupon the slowreleasinp; line relay. LR is energized over a? circuit extending from grounded battery, winding of the line relay Llii outer left hand back contact and armature ofthe relay Qctip conductor 3 0f the calling line, through the calling substation circuit, ring conductor 4, and inner armature and back contact of relay 2, toground Line relay LR is energized in this circuit and closes a circuit through the left handwinding of relay 2, which attracts its arms.-

I ture, causing the plunger 5 to bring the contacts of the calling line and an idle trunk into engagement. The operation of the plunger 5 besidesclosing the line and trunk contacts, causes contact 6 to extend ground to conductor 7 for a purpose to be described, and causes the spring 8 to close a break point in the test circuit. As soon as the calling line is connected to the idle trunk disclosed, the stepping relay SR is energized over a circuit completed through the two sides-of the trunk and calling line in series. The stepping-relay SR attracts its armature to close a circuit for the slow releasing relay 9 in the wellknown manner. This relay 9 is so adjusted that it does not retract its armatu'res. when its energizing circuit is momentarily interrupted, butresponds only to a long interruption of this circuit, At the left hand 'armature and front contact of the relay 9, when" attracted, ground is connected to the test conductor 11 which serves as a guarding potential to prevent-the seizure of the call- 1 ingsline by any connector. This ground is alsoconnected through spring 8 to maintain energizedflthe righthand Winding of relay 2 which serves to hold the plunger 5 actuated until the time of release. Thls same ground'is also effective to operate the master switch to preselect an idle trunk for the next call to be originated'in a manner disclosed in the above mentioned line switch patent.

The connector switch is now in condition to be directivelyoperated in response to impulses transmitted from the dial of the calling substation. Inresponse toeach of these impulses, corresponding to the tens digit of the wantedi'number, the stepping relay SR operates its armature and at its back contact closes a circuit from ground,-arma-' ture and front contact of relay 9, slowreleasing relay 10. winding of the primary motor vmagnet PM, side switch wiper 11 in its first position, to grounded battery. In

response to each closure of this circu1t, the' primary motor magnet is; operated and advances the connector switch one step 1n its group selecting movement. The slow-releas- "ing relay'lO is energized in the circuit just described, and is" maintained energized until theiclosing of the tens series of impulses, and thus'completes an energlzing clrcuitfor i i; the escape magnet ESC, from grounded batof the tens series'of impulses, the slow-- tery, resistance, winding of this magnet,

continuity spring and armature of slowreleasing relay 10, to ground. At the close releasing relay 1O retracts its armature and opens the energizing circuit of the escape magnet ESC, just described, causing this magnet to move the side switch wipers'into their second position.

In'response to the o perationof the dial i at the substationtA corresponding to the units digit ofthe wanted number, the step-.'

ping relay SR again vibrates itsarmatures,

but in this instance it'controls the secondary magnet SM, over a circuit traceable from. grounded battery, side swltch wiper 11 n its second pos1t1on, winding of the secondary magnet, outer right hand back contact and armature of thetest relay TEST, winding of the slow-releasing relay 10, right hand front contact and armature of relay 9, back contact and armature of relay SR to ground. In response to the first closure of this cir cuit just described, the escape magnet ESC is operated over the circuit previously de scribed as extending from grounded gbattery, resistance, winding of the escape magnet ESC, continuity spring and armature of relay 10, to ground. In response to each re traction of the armature of the stepping relay SR, the secondary motor magnet SM is operated to advance the connector switch in the group of lines previously, selected during the group selectingmovement.

At the present stage of the description it will be'assumed that the wanted line is idle. Under this assumption 1 at the close of the units series of impulses, the relay 10 will retract'its armature and thus interrupt the operating circuit of escape magnet: ESQ, causing this magnet to move the side switch wipers into their third or signaling position.

In-acoordance with the present invention,

means are provided-in the case of calls originating in one group of lines to signal a called station 1n a distinctive manner.

that the call originated at the station of the party requiring an especially prompt response to his calls. In this case the spring 6 corresponding to his line at his line switch is connected to ground so that when the plunger 5 operates, a circuit was extended from ground, through the spring 6 and its contact, conductor 7, and winding of the relay 1 1, and when the side switch Wiper 11 reaches its third position, this circuit is completed to grounded battery. Relay 14 is energized in this circuit, and closes a signaling circuit from grounded battery, re sistance, generator 15, interrupter 12, front contact and armature of relay 14, winding of the trip relay TRIP, side switch wiper 416' inits third position, connector brush 17,

through the called subscribersline and substation circuits, connector brush1 18, side tained energized in this circuit until thecal l-eo party responds. whereupon the margin al trip relay TRIP, is energized in the well. known manner, and attracts its armature. The escape magnet ESC is thus short circuited by a round at the armature oi the trip relay 'l lllil and deenergizes to move the side switch wipers into their fourth or talking position. Guarding potential is supplied to the test terminal of the wanted line from ground, side switch wiper 21 in its fourth position and connector test brush 22. Talking battery 15 supplied to the callsubscriber through the windings or the stepping relay SR, while talking battery supplied to the called subscriber through the windings of the impedance coil 23.

If the call. had originated at some substation which is not entitled to this, special service, the spring 6 of the line switch of this lin would not be connected to ground, so that when the side switch wiper 11 moved into its third position, no operating circuit would be completed for the relay 1t and signaling current would be supplied to the wanted station through the interrupter 13 with the resulting operation of the l ell at the called station in the ordinary intervals of ringing and silent periods.

Let it be assumed that the wanted line is busy when the connector brushes 1?, 18 and.

. 22 are placed in engagement with its multiple terminals when the slow-releasingr relay 10 deeuergized at the close of the units series of impuses, a substituted operating circuit torthe escape magnet ESC is then completed from grounded battery, winding of the escape magnet ESQ, continuity spring; and contact ofrelay 10, winding; of the test relay TEST, continuity spring and contact of this relay, side switch wiper 21 in its sec end position, test brush 2?) of the connector through a multiple terminal of the wanted line, through a test brush corresponding to in its third or fourth positions to ground at the connector which has seized the called line. The test relay attracts its armatures and at its inner right hand armature and continuity spring closes a locking circuit for itself to ground through the off normal con tact and spring 23. At the left hand armature and front contact of the test relay, a circuit is closed for applying a busy tone to the calling line from the busy machine BZ.

When the calling subscriber replaces his receiver on its switchhoolr, the energizing circuit of the stepping relay SR is interrupted, and shortly after this the slow-releasing relay 9 retracts its armatures. At the l ght hand armature of this relay a circuit is closed tor the relr-iase magnet REL ot the connector, from grounded battery, winding" of this magnet, off normal. spring, and contactQ l, back contacts and armatures ct relays and Sihto ground. The releasin magnet REL operates in the well known manner to restore the brushes and appa ratus of the connector to normal position. At the left hand armature and front contact, the holding circuit for the relay 2 e):- tendinc; over conductor 11 is interrupted and permits the plunger 5 to be withdrawn from the contact bank, andin due course 01": time the plunger is placed under the control of a master switch to be positioned before terminals'ot idle trunks. The apparatus is new in condition for completing; successive calls. 7

lVhile no selector switches have been disclosed in the present showing, it will, be readily understood that if the invention incorporated in larger systems such switches will be employed.

,Vha't I claim is 1. In an automatic telephone system, plurality of subscribers lines of different classes, means inclucing final connector switches for interconnecting said lines, a trunk terminating at each of said .tehes, a signaling device associated with each subscribefls line, and means for discriminating; in which class of lines a call orioinates for variably operatingsaid Signahngrdevices.

2. In an automatic telephone system, a

plurality of telephone lines, each of said lines being; arovided with a signaling device, means including]; automatic switches for in tercounectiug said lines oi" ditierent cla. s a s" ogle trunlr extending to each autom ti 7.

switc 1, two sources of signaling); current ofdiiferent character. and means for discrimieating; in which class of lines a call origis nates for selecting signaling current of the proper character.

3. n1 telephone exchange s stem, subscribers lines, a signal associated with each line, on automatic switch wherein said lines terminate, a single trunk terminating at said switch, means for causing said switch to select a line, and means automatically operated by the selection or". one of said lines for variably operating the signal thereof.

t. In a telephone exchange system, sul scribers lines, a connector in which said lines terminate, a single trunk terminating at said connector, means for causing said connector to select adesired line, sources of signaling current of different character, relay automatically operated by the seizure of said trunk for selecting signaling current of the proper character.

' 5..In a telephone exchange system, sue

scribers lines of different classes, a signal associated with each line, a connector in which said lincsterminate, a single trunk line terminating at said connector,-means for setting said connector on said lines over said trunk, a signaling circuit associated with said connector, a relay at said connector controlled by the character of the calling subscribers line, to control said signaling circuit, and sources of current of different character controlled by said relay.

6. In an automatic telephone system, a plurality of telephone lines of different classes, means including automatic switches for interconnecting said lines, signalling devices associated with each of said lines, two sources ofsignalling current of diilerent characteristics and means controlling the application of said sources of signalling current to said signalling devices and a circuit independent of the talking conouctors of said telephone line over which said means is controlled.

7.1n an automatic telephone system, a plurality of telephone lines of different classes, means including automatic switches for interconnecting said lines, signalling devices associated with each of said lines, two sources of signalling current of different character and a relay controlling the application of said sources of signalling current to said signalling devices and a circuit independent of the talking conductors of said telephone lines over which said means is controlled. p

8. In an automatic telephone system, a, plurality of telephone lines, means including automatic switches for interconnecting said lines, signalling devices on each of said.

lines, two sources of signalling current as sociated with certain of said automatic switches and means arranged to be automatically controlled from the calling line independent of the talking conductors of said line to apply one or the other of said of signalling current a wanted applying signalling current of the desired 3 character. 7 v Y 10. In an automatic telephone system, a plurality of telephone lines of different classes, each provided with a signaling device, a group of trunks, agroup of connector switches, each trunk terminating in a connector switch, a single group of trunk selecting switches individual to said group of trunks, means including a trunk selecting switch and a connector switchfor interconnecting calling" and called telephone lines, and means for discriminating in which class of lines the call originates for variably operating said signaling device.

11. In an automatic telephone system, a plurality of telephone lines. of ditlerent classes, a signal for each telephone line, means including a connector switch for interconnecting said lines, a trunl: circuit, a single pair of conductors bridged to the incoming end of: said trunk, an impulse relay connected to said brid 'cd conductors for controlling the operation of said connector switch, two sources of current of different character and means for discriminating in which class of lines the call'originates for selecting signaling current of the proper character to operate the signal of a called line. i

In witness whereof, I hereunto subscribe my name this 14th day of July A. D. 1919.

VINFRED Cl. POlVELL. 

